1. The Field of the Invention
The present invention is generally directed to agricultural irrigation systems, and more particularly, it is directed to novel apparatus for controlling irrigation valves.
2. The Prior Art
Since it became a desirable and generally accepted practice to transport various liquid and gaseous materials by pipeline, methods have been required for controlling the flow of those products within the pipeline system. Pipelines of various types are, of course, widely used in a variety of fields. For example, energy pipelines of various types are found in every region of the country and carry such products as natural gas, oil and natural gas liquids from their point of production to the point of end use. In addition, in attempts to increase the amount of farmable land surface, water has become another product which is commonly carried by a pipeline.
In arid and semi-arid environments, such as those existing generally in the western United States, production of various crops depends upon the ability to transport water to those crops. Rain fall in these areas is relatively sparse, commonly not exceeding approximately 10 inches per year. As a result, in order to grow most agricultural crops it is clear that water must be transported to the farm from a remote location.
Since the colonization of the western United States in the late 19th century, it has been a common practice to use irrigation as a method of supporting agricultural production. Irrigation systems began as a simple series of canals and ditches which were capable of taking water from springs or streams and transporting it to the field. Since that time irrigation systems have become much more sophisticated.
Many irrigation systems are currently comprised of complex systems of pipes which are able to carry water from a central source to the field. For example, a typical irrigation system may include a large main water line of up to 12 inches in diameter. Such main lines may easily carry 1,000 gallons of water per minute or more. These main lines are then fed into various smaller branch lines until finally the water reaches a small distributor line, possibly accompanied by a sprinkler at the terminal end. These smaller lines may typically carry approximately 150 gallons of water per minute.
It will be appreciated that it is critical to control the flow of water through the system. The farmer must have efficient equipment and methods to direct needed water to particular areas of his farm and to stop the water flow to areas which have sufficient irrigation water.
It is not uncommon for a farm, particularly in the western United States, to be comprised of several hundred or even several thousand acres. As a result, it will be appreciated that the task of irrigating such a farm is substantial. As a result, various valve systems have been developed which help to mechanize the task of irrigating crops by controlling the flow of water through the irrigation system.
It is now common practice to use electrically controlled valves on the various water pipelines used in irrigation systems. This allows a farmer to irrigate his crops automatically through an electrical system which controls the various valves. The farmer is provided with the ability to remotely, and even automatically, direct a predetermined quantity of water to a predetermined location on his farm.
While such systems have many advantages, when valves are operated remotely by an electrical control means, it is clear that the farmer is not able to check the condition of each valve as it is operated. Thus, dirt and other contaminants may enter the valve and associated motor without detection. The motor and valve may thus be operated while the contaminants are in contact with the mechanism. As a result, the potential for damage to the valves and associated motor assemblies is great.
It is the current practice in most conventional irrigation systems to employ a valve which is controlled by a small electric motor. The motor is connected to the main electrical control system so that the valve can be opened and closed remotely. The typical motor which is now in wide use is a 1/8th horsepower electric motor. The gears associated with the motor are generally made of a type of plastic such as nylon or teflon. Unfortunately, the motors used in the prior art are not currently equipped with adequate safety shut-off control mechanism. As a result, if dirt or other types of obstructions enter the gears or the associated valve, the small motor will continue to turn until either the motor is damaged or the gears are rendered unusable.
A significant problem with such motor and valve assemblies is that they do not employ conventional replaceable parts. Thus, when a gear or motor is damaged, it is not practical to attempt to replace the damaged part; as a result, the entire motor and assembly must be removed and replaced with a new motor and assembly. It will be appreciated, therefore, that the use of such a motor and assembly rapidly becomes very expensive.
It is apparent that what is currently needed in the art is a more durable and reliable valve control mechanism than those which have been available in the past. It would be an advancement in the art to provide a valve control mechanism which could remotely control a valve, yet had safety features built in which would protect the valve and control mechanism from damage. It would be a further advancement in the art to provide such a valve control mechanism which employed conventional and inexpensive parts which could be easily replaced if necessary.
It would also be an advancement in the art if such a valve control mechanism had a conventional manual method of turning the valve on and off. And, mentioned above, it would be a significant advancement in the art to provide a valve shut-off mechanism which included a safety feature which would prevent damage to the mechanism in the event any part of the mechanism became jammed or clogged. Such an apparatus is disclosed and claimed herein.